Do you wish your teeth were less yellow and had fewer stains? You’re not alone: Teeth whitening is a common topic patients ask dentists about, says Dr. Samantha Rawdin , a prosthodontist at Gallery 57 Dental in New York City. Whitening toothpaste cleans teeth and helps prevent cavities, plus has ingredients that help remove surface stains. But how well does it work? “You’re not going to notice anything dramatic,” says Dr. Amr Moursi , a professor at New York University’s College of Dentistry.